Geothermal Collection Reservoir

Some Aspects Believed to Be Geologic Components of Eastern BBHSP

As we continue to face the challenge of maintaining the health and stability of the hot springs, hot wells, and hot seeps along the river banks at BBHSP, we have been learning a lot over more than a decade, and we continue to try new ideas and learn more. The hydrogeology and thermodynamics of the hot water aquifer is very complex and little is known about its underground areas and flows. We want to protect the natural hot springs and make sure the springs and wells are safe for the natural geothermic flows. We have put a lot of thought, prayer, observation, data collection, professional consultation and reports, hydrogeologic study for more than a decade, and we still learn more each season. One of our main priorities is to improve the hot water collection system at the spring known as “The Mother Source”, which has numerous leaks and seeps and pipes that need to be cleaned up and collected in a central reservoir for the most efficient use.

Improving The Mother Source Containment Vessel (“MSCV”):

The Mother Source Containment Vessel (MSCV) is an old wooden and concrete box (probably built in the 1930s or 1940s?) that channels most of the water in its hot spring location into a useable vessel reservoir (about 5′ square), but it is in a state of deterioration and has many leaks underneath the box and in various cracks and seeps. Our goal is to repair it and help contain and direct the hot water, for more efficient use and less river bank erosion:

Approximation MSCV existing design drawing by Dan Plankenhorn. in 2010

Big Bend Hot Springs Project is working on improving the MSCV for the sacred hot spring (Madesi name is apparently Lah-lah-Pis-Mah Hot Springs). The springs are located along the region’s major geologic fault line (a crack in and below the bedrock that runs mostly along the ISS Creek and the Pit River), where minor fault lines also intersect with the major fault line, and this is where the hot springs are allowed to flow up to surface levels.

Rough examples of major and minor Geologic fault lines near creek and River where several fault lines intersect (main intersection shown at orange arrow).

At least four exploratory geothermal wells (on both sides of the Pit River) were drilled without much success in 1988, but one of them is very productive and useful (Artesian Hot Well #1, at 1200 feet depth!). The other geothermal wells do not seem productive, so we are considering drilling another Hot Well, to access more of the hot water, to increase the amount of electricity we can generate from the excess scalding heat.

Approximate elevations, temperatures, and flow rates of various BBHSP water sources in 2011

These elevations were obtained by using an adjustment factor of 690 feet higher than the professional surveyors, who used the corner property marker as a baseline guide (at 1,000 feet), and surveyed everything, using that as a base of reference. So it appears that that actual base point is not 1,000 feet above sea level, but actually 1,690′. We are in the process of double checking this elevation data with local topographical maps, Google Earth, and GPS technology.

New (2016) well head of Hot Well #1 (drilled 1988), to prevent leaking from corrosion.

Among the various sources, the water temperatures and the GPM (Gallons Per Minute) flows are fairly consistent, but with some seasonal variations and apparent changes in the mysterious underground hydrogeology. The Mother Source, for example no longer seems to produce 80 GPM at the outflow pipe on the containment box, because decades of erosion has undermined the containment seals, so there is a lot of water leaking out from under the box. There are also numerous seeps around and below the Mother Source, so we are looking into creating a small dam and collection reservoir several feet below the Mother Source, in which most of the geothermal seeps of that spring could be collected for energy, heating, and soaking use with maximum efficiency.

The MSCV (Mother Source Containment Vessel), about 2010, before some improvements…

Our challenge is to create an unobtrusive collection reservoir below the Mother Source and associated seeps, so we can get the maximum water to use for power -generation, heating, and soaking, before returning it to its natural flow back down the river bank and into the river. We will keep you posted about new design ideas and progress!

Mother Source Site: BBHSP Removed a large unpermitted building at the site back in 2008

Mother Source:
To get gravity flow going down long white Pex pipe to the small terrace with the claw foot tub deck (slightly down river with slight elevation drop), we needed to raise the level of the water in the MSCV (Mother Source Containment Vessel), so the overflow would come out of the higher pipe, since we need every inch of increased elevation possible for more effective gravity-feed system.

We successfully installed a (temporary) re-plug into the termination end of lower outflow pipe (after towel with rock inside finally failed).  The interior diameter of lower outflow pipe = 4.5” (pipe appears to be slightly disfigured, but a plastic bowl with duct tape layers worked well, but needed heavy rock to lean on it and keep it from blowing out, as interior pressure increased).

In the picture below, you can see the lower plug (yellow-green bowl with rock leaning on it), and the water coming out of the top pipe. What’s less visible is the many GPM that are leaking out, below the bottom (now plugged) pipe, and under the concrete wall, which frames the spring box top, and holds the outflow pipes in place.  There is also some water leaking from cracks in the box rim (one has a rag shoved in it below the top pipe but it continues to leak, at a reduced rate).

MSCV Problems: 
We used to get 80 GPM of 180ºF water from this vessel/pipe.  Over the years, things have changed.  The water has found some new paths of least resistance under and around the MSCV, so it’s difficult to capture or channel higher volumes until we somehow repair the MSCV.  Besides the plentiful Mother Source water leaking out from under the concrete box, there are also some hot seeps near the MSCV that seem to have increased their flow over the years.  

There is also a pipe that drains the flows under the slab of the old bathhouse (torn down and removed in 2009), that looks like it’s running at about 7 GPM (?).  Here are the data collected in December of 2020, while working on re-activating the Claw Foot Tubs at dusk (Ambient Outdoor Temperature: 33ºF):

•Mother Source Water Temperature in Box (no lid): 179ºF
•Mother Source Water at Top Pipe Outlet: 178.5ºF

Other Mother-Source-Related Hot Water Nearby:
1. Seepage puddle pool near Mother Source: 171ºF (4-5 GPM?)
2. Slab drain outlet pipe (under Reservoir Tub): 169ºF (5-7 GPM?)

Mother Source to Claw Foot Tub Gravity-Fed System:
•Mother Source Water Temperature in Box (no lid): 179ºF
•Mother Source Water at Top Pipe Outlet: 178.5ºF
•Water exiting open-air aqua duct system: 162.6ºF
•Reservoir tub by intake pipe (top of pex line): 153ºF
•Bottom of Pex line (output at Claw Foot trough: 145ºF
•Water in distribution trough at Claw Foots: 143ºF
•Claw Foot slow fill setting: 130ºF
•Claw Foot fast-fill setting: 138ºF

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